Re: [PATCH v3 0/6] cpufreq: schedutil: fixes for flags updates

From: Peter Zijlstra
Date: Wed Dec 20 2017 - 13:16:30 EST


On Wed, Dec 20, 2017 at 06:38:14PM +0100, Juri Lelli wrote:
> On 20/12/17 16:30, Peter Zijlstra wrote:
>
> [...]
>
> > @@ -327,12 +331,7 @@ static unsigned int sugov_next_freq_shar
> > if (delta_ns > TICK_NSEC) {
> > j_sg_cpu->iowait_boost = 0;
> > j_sg_cpu->iowait_boost_pending = false;
> > - j_sg_cpu->util_cfs = 0;
> > - if (j_sg_cpu->util_dl == 0)
> > - continue;
> > }
>
> This goes away because with Brendan/Vincent fix we don't need the
> workaround for stale CFS util contribution for idle CPUs anymore?

Oh, good point, no I took that out because of:

@@ -314,6 +315,9 @@ static unsigned int sugov_next_freq_shar

unsigned long j_util, j_max;
s64 delta_ns;

+ if (j_sg_cpu != sg_cpu)
+ sugov_get_util(j_sg_cpu);
+
/*
* If the CFS CPU utilization was last updated before the
* previous frequency update and the time elapsed between the


which recomputes the util value all the time. But yes, that still needs
those other patches to stay relevant.